I. Field of the Invention
This invention relates to window shade support apparatus and a method for manufacturing the apparatus. More particularly, the invention relates to an improved and simplified shade roller spring motor assembly, in which the drive spring is connected through a ball clutch to a spear by means of a greatly simplified apparatus and method of fabricating the assembly.
II. Background
Window shade support apparatus including a motor drive spring connected to a spear through a ball clutch is known in the prior art. Typically, the end of the drive spring remote from the spear is non-rotationally fixed in the far end of a dowel over which the spring is telescoped. The dowel is usually attached to a spear which in use is non-rotationally received by a mounting bracket. The end of the drive spring nearest the spear is connected to a rotating portion of the shade roller apparatus. Typically, numerous components have been required to assemble the spring motor and implement its connection of the drive spring to the rotating portion, as well as to form the clutching arrangement between the rotating portion and the non-rotating spear, to enclose the spear and the clutching apparatus, and to attach a dowel to the spear. Each of these components must be separately fabricated and handled, and then laboriously assembled into the completed product.
For example, U.S. Pat. No. 659,584 issued to E. C. Cordes on Oct. 9, 1900 teaches a spring shade roller having a shaft, a collar with pockets, a disc with a recess, a cap and securing means for the cap. The disc has lugs which are attached to the end of the spring drive nearest the spear. It can be appreciated that a reduction in the number of pieces required to fabricate a shade support and a corresponding simplification of fabrication would be desirable. Further, improving the securing means for the spear end of the driving coil to simplify fabrication is desirable.
U.S. Pat. No. 375,986 issued to G. T. Briggs on Jan. 3, 1888 teaches a spindle with a tapering ferrule and with an annular groove or channel for receiving the end nearest the spear of a coiled driving spring. Similarly, U.S. Pat. No. 1,329,992 issued to A. R. Nelson et al. on Feb. 3, 1920 and U.S. Pat. No. 1,803,042 issued to T. B. Thurman on Apr. 28, 1931 teach a drive spring coil slipped over a spindle with no inward radial compressive retaining force on the spring. It would be desirable to have a positive compressive force on the drive spring to better secure the spring from turning on the spindle or from slipping off the spindle. Additionally, the aforementioned patents teach fabricating the shade support roller using a multitude of parts such as sleeves, tubes, shafts, supporting brackets, nail-like protrusions, washers and caps. Again, it would be desirable to reduce the cost of manufacture by reducing the number of parts and simplifying the assembly process.
U.S. Pat. No. 3,763,916 issued to R. C. Gossling on Oct. 9, 1973 teaches a window shade motor which includes an allegedly improved connection of the spear end of the drive spring to a rotating portion of the shade roller. As before, the spring is slipped over a spindle. However, in addition, the drive spring includes a bent portion near its end which engages a recess in a body element of the window shade motor. The end of the drive spring, just beyond the bent portion, extends into and engages the inside of the roller wall. Accordingly, the inside of the roller wall applies a loading force to the end of the bent portion to keep the bent portion in the recess. It would be desirable to more evenly distribute any compressive force over the secured end portion of the driving spring to better retain the driving spring. Further, it would be desirable to simplify the apparatus and fabrication of the window shade support.
It is an object of this invention to simplify the apparatus of a shade support assembly and to reduce the number of parts in such an assembly.
It is a further object of this invention to simplify the manufacturing process used in window shade support roller assembly, thereby reducing the time required to assemble the support assembly and reducing the labor and expense required by manufacture.
It is thus a major objective of this invention to provide a new type of shade roller construction having greatly improved simplicity of structure, durability, and economy of manufacture, together with a new method of manufacturing such an assembly.